Dual demodulating circuit tracer

摘要

A non intrusive circuit tracer for positively identifying a conductor at position remote from a point of injection of a test signal. Tracer signal is alternately injected into two conductors at a rate of alternation which is substantially less than the tracer frequency. At another point along the conductor signal is sampled and synchronously demodulated first with respect to the tracer frequency and then with respect to the rate of alternation of the tracer frequency between conductors.